5. Heart Sounds
Auscultation: The act
of listening to sounds
within the body.
Four Sounds:
* S1-Lubb
* S2-Dupp
* S3 & S4
Produced due to:
* Vascular
* Muscular
* Valvular
7. INTRODUCTION
Presence of noise in PCG signals effect
the quality of sound.
Aim of PCG is to provide a
complementary tool to record heart
sound and murmurs.
An effective noise elimination can be
obtained using an adaptive filter.
8. COMPONENTS OF THE DEVICE
PCG microphone
Adaptive Filter
Analogue to Digital
Converter
Microcontroller
Output Device
9. WORKING
PCG Microphone:
- air-coupled sensor which measures
pressure waves induced by chest wall
movements.
- To acquire PCG signals
10. •Adaptive Filter
-Function: Elimination of noise components.
-It is a filter that self-adjusts its transfer
function according to an optimization
logarithm driven by an error signal
11. PCG feature extraction using DWT
Cardiac
cycle
DWT
db 4,5 levels
From
PCGs
Extraction &
Classification
Modification
IDWT
Db 4,5 levels
Generates Heart Sounds
12. •Analogue to Digital Converter
- A device that converts a continuous physical
quantity to a digital number that represents
quantity’s amplitude.
- Here, the filtered PCG signals are converted
into digital form.
13. •Microcontroller
- A small computer on a single ‘integrated
circuit containing a processor core, memory
& programmable I/P-O/P peripherals.
- 16-bit MSP430F5438 is used.
- Programmed to give an alert(o/p) on
occurrence of abnormalities.
14.
15. INPUT PC SIGNAL
Method for the estimation of the splitting interval (SI) between the aortic (A2)
and pulmonary (P2) components of the second heart sound (S2).
16. ADVANTAGES
Versatile
Portable
Cost effective
Superior noise cancellation
USES
Acts as Pre-indicator for abnormal heart.
Helpful in rural areas, in absence of
cardiologist for further diagnosis.
Can provide clues of the cause of heart
disease/failure.
17. CONCLUSION
It is pertinent to consider a time
sequence of patient data.
Better recording of the desired signal can
be obtained.
Provides valuable information about
functional integrity of the heart.
Thus, has high potential for detecting
various heart diseases.